Living laser and Optical Biochip
The optoelectronic material of the future will have to support a variety of functions on a single chip.
In some cases this will involve complete integration of a system on a chip, in other cases it will mean components with additional functionality or with properties tailored to suit the application. The pinnacle of our ambition is to produce truly integrated platforms in which biology, optics and structure combine to give a holistic system read-out. This involves the exploration of the physics of the light matter interactions in the constituent materials and devices.
By integrating epitaxial absorption layers within laser diode structures we have produced devices with internal optical feedback. This leads to bistable operation resulting in a train of sub-ns optical pulses with a current-tunable periodicity. We have demonstrated that using a tunable ‘stroboscopic’ excitation of this kind fluorescence lifetimes can be measured using time-integrated detection thus high speed dynamics can be studied with long detector integration times ensuring high signal-to-noise ratios.
- Thomas, R. 2012. Monolithic coupled-cavity laser diodes for bio-sensing applications. PhD Thesis , Cardiff University.
- Holton, M. D. et al., 2009. Stroboscopic fluorescence lifetime imaging. Optics Express 17 (7), pp.5205-5216. (10.1364/OE.17.005205)
- Edwards, G. , Smowton, P. M. and Westwood, D. I. 2008. Dry etching of anisotropic microstructures for distributed bragg reflectors in AlGaInP/GaAs laser structures. IEEE Journal of Selected Topics in Quantum Electronics 14 (4), pp.1098-1103. (10.1109/JSTQE.2008.918260)